Reproductive parameters in M and K group chimpanzees during 35 years (1966-1999)
Reproductive parameters N Mean SD Range
Age at first maximal swelling*1 (yrs.) 5 10.63 0.51
Adolescent infertility*1*2 (mo.) 4 14-49
Age at first birth (yrs.) 5 15.60 4.52
Age of emigration from natal group*1(yrs.) 11 11.27 1.50 9.7-14.0
Time between immigration and first birth*1 26 3.34 2.53 2-11.9
Afterbirth interval (yr.) (previous offspring: male) 15 6.04 0.70 5.25-7.25
                            (yr.) (previous offspring: female) 18 5.52 0.63 4.33-6.50
The number of live birth during lifetime 26*3 3.85
25*4 2.68 1.25
The number of weaned offspring during lifetime 26*3 1.35 1.23
25*4 1.96 1.06
The age at final birth (yrs.) 35 @ @ 22-47
*1 The four parameter are related to the age at first birth.
*2 The period between the time of the first maximal swelling and the first birth
*3 The birth record is available from a young age (10-13 yrs.) to death at various ages.
*4 The birth record is available from middle age (18-33 yrs.) to death in older age (31-48 yrs.).
Source:
[67] Nishida T., Corp N., Hamaib M., Hasegawa T., Hiraiwa-Hasegawa M., Hosaka K., Hunt K.D., Itoh N., Kawanaka K., Matsumoto-Oda A., Mitani J.C., Nakamura M., Norikoshi K., Sakamaki T.,Turner L., Uehara S., Zamma K. (2003) Demography, female life history, and reproductive profiles among the chimpanzees of Mahale. Am. J. Primatol. 59: 99-121
[72] Nishida T. (2002) Demographic changes. In: Nishida T., Uehara S. & Kawanaka K. (ed.) Thr Mahale Chimpanzees: Thirty-seven Years of <Pantropology>. Kyoto University Press, Kyoto. Pp 171-202